The present invention relates to an improved method and apparatus for filling in the audio blanks in a message as received by a receiver resulting from switching the receiver between a plurality of input channels each having a different message for selecting the channel of highest priority.
In a radio receiving system with multi-channel input capability, the input channels are often assigned an order of priority with respect to the importance of the messages that are to be received. When a channel is in use and another channel of higher priority becomes active, important benefits, including improved receiver efficiency, would be gained if the receiver could sense the activity of the higher priority channel and automatically switch from the first channel to the one of higher priority.
Due to redundant characteristics of normal speech when observed in short segments of, for example, between 1 and 250 ms, it is possible to periodically remove a small portion of these segments without losing the intelligibility of the speech. A receiving system could utilize this phenomenon to allow it to periodically switch from a channel in use to one of higher priority and to make a decision to return to the original channel if the higher priority channel is inactive or may be switched to remain connected with the higher priority channel if that channel is active. Although this type of speech interruption does not significantly reduce intelligibility, the resultant loss of small speech segments is obvious to the ear and can result in fatigue for some listeners.